The present invention relates to a moving object displaying method which extracts an object which moves in the view of a monitoring camera, etc., from an image which an imaging camera produces and displays it on the display device, a display system which uses the method, and a program recording medium therefor.
Monitoring of video produced by imaging cameras is executed in various places such as roads, railroad crossings, dams and convenience stores. These aim to prevent occurrence of the accidents and the crimes by observing the objects which appear in such specific places. Suspicious-looking persons are monitored, for instance, in convenience stores, and it is monitored whether human beings invade in those areas like the dams where the invasion is absolutely prohibited. It is now general that such monitoring is executed in such a manner that a person watches the video in real time or that the video is recorded on the storage medium like a video tape and is checked afterwards, so the monitoring is time-consuming work. The automation of the video monitoring with a computer is requested from such circumstances. Various methods have been proposed so far.
The article by H. Nakai et al., "Detection of Moving objects with Three Level Continuous Modules", Transactions of the Institute of Electronics, Information and Communication Engineers, D-II, Vol. J77-D-II, No. 7, July 1994, pp. 1209-1218 (hereafter called the first reference document), proposes a method of automatically detecting a moving object like a pedestrian etc. from a video by using the continuous processing module of three steps like detection of change, partial trucking, and movement interpretation. It also reports a result of an experiment to extract moving routes of passengers in a general shop. The article by T. Nakanishi et al., "Automatic Vehicle Image Extraction Based on Spatio-Temporal Image Analysis", Transaction of the Institute of Electronics, Information and Communication Engineers, D-II, Vol. J77-D-II , No. 9, September 1994, pp. 1716-1726 (hereafter called the second reference document), proposes a method of automatically extracting vehicles such as cars which run outdoors, by using the time space image processing. The Japanese laid-open patent application No. 8-221577 or its corresponding U.S. patent application Ser. No. 08/601,951, now U.S. Pat. No. 5,721,692, assigned to the present assignee proposes a method of detecting a moving object in outdoors, which sets a slit in an image, calculates correlation of the current image with the image of the background stored beforehand, detects a change in the image, thereby to detect a moving object. Systems are already in the market, which can monitor moving objects in outdoors, for example, a system of automatically recognizing car numbers of running cars.